Parallel and Distributed Simulation Systems

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Parallel and Distributed Simulation Systems

• Richard Fujimoto
• College of Computing
• Georgia Institute of Technology
• fujimoto_at_cc.gatech.edu

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Parallel Distributed Simulation Systems

• We study issues concerning the distributed
  execution of simulation programs over multiple
  computers
• Multiprocessors, clusters of workstations, ...
  global Internet
• Rationale
• Get answers faster, or more detailed models
• Scalable real-time systems (e.g., millions of
  on-line users)
• Geographically distributed users / resources

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Historical Perspective
High Performance Computing Community
SIMulator NETworking (SIMNET) (1983-1990)
High Level Architecture (1996 - today)
Distributed Interactive Simulation
(DIS) Aggregate Level Simulation Protocol
(ALSP) (1990 - 1997ish)
Defense Community
Dungeons and Dragons Board Games
Multi-User Dungeon (MUD) Games
Multi-User Video Games, Large-scale Internet
Gaming
Adventure (Xerox PARC)
Internet Gaming Community
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Research at Georgia Tech

• People
• Faculty Fujimoto, Ammar, Riley (ECE), Schwan
• 2 research scientists, 7 PhD students, 2 MS
  students
• Current Projects
• Parallel simulation emulation of communication
  networks
• COMPASS Composable, Parallel, Simulation of
  Networks
• NETS (with UCLA, SPAWAR)
• Network Emulation Backplane
• Distributed real-time simulation
• Distributed Hardware-in-the-Loop
• DoD High Level Architecture
• Embedded systems
• Distributed simulation over wireless networks
• Parallel simulation of mixed-signal circuits

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Parallel / Distributed Simulation Software

• We build middleware that sits between the
  OS/hardware and simulation applications
• Services for simulations in general, not a
  particular domain
• Work with domain experts, customize as needed
• Parallel/distributed computing issues

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Run Time Infrastructure Software
RTI Ambassador Implementation
TSOQueue
ROQueue
MB_Buffer
FedState
RTI State Info
DRTI Implementation
DRTI Auxiliary Classes
RTICore
FedInfo
InstInfo
FedParser
RegionInfo
HVPSImpl
other support libraries
MCAST
TM-Kit
DDM-Kit
FM-Kit
Shared memory
IP protocols
Myrinet
Physical Network
Middleware implementing services for distributed
simulations
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A Typical Problem Synchronization

• Things happen in the real world in a certain
  order (e.g., cause effect).
• It should appear that events in the simulated
  world happen in the same order as the real world
  actions that they represent.

simulated world
real world
fire
event message
Simulator A (tank)
Simulator B (target)
target destroyed
Simulator C (observer)
Time (wallclock time)
If the fire message is delayed in the network,
the observer will see the target is destroyed
before the tank fired upon it! The distributed
simulation executive must provide services to
avoid temporal anomalies such as this
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Some Current / Recent Research

• Large-Scale network simulation
• Rapid parallelization of sequential network
  simulators (pdns)
• Composable network simulators
• Simulation of large networks (e.g., the Internet)
• Cloning running parallel simulation programs
• Reverse execution of programs
• Updateable simulation programs
• Distributed simulation middleware
• Quality of Service for distributed simulations
• Data distribution in virtual environments
• Distributed simulation over wireless networks
• Experimental research We build systems

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How to get involved...

• Check out our web site
• http//www.cc.gatech.edu/computing/pads/
• Come talk to us
• Fujimoto (319 CCB, fujimoto_at_cc.gatech.edu)
• Postdocs, research scientists, students
• Mini-projects
• Distributed simulation middleware
• Network simulation / emulation

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The Georgia Tech Modeling Simulation Research
and Education Center (MSREC)
MSREC's mission is to create and support
cross-disciplinary research and development
activities, including research in core M S
areas, supporting technologies, and innovative
applications. It will develop and maintain
education programs to train M S practitioners,
educators and researchers.
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Participants

• College of Computing
• College of Engineering
• Aerospace Engineering
• Civil Engineering
• Electrical Computer Engineering
• Industrial Systems Engineering
• Clark-Atlanta University
• Georgia Tech Research Institute

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Research Emphases (Selected)

• Advanced Engineering Design Environments
• Large-Scale Communication Networks
• Distributed, Real-Time Computing
• E-Commerce, Supply Chain Management
• Embedded Systems
• High Level Architecture, Defense Applications
• Human / Machine Interfaces and Systems
• Intelligent Transportation Systems
• For more information http//www.msrec.gatech.edu